geom(4): Fix some of the "set but not used" warnings

The few I've left in place look like potential bugs.

Sponsored By:	EPSRC

sys/geom/bde/g_bde.h

@@ -57,6 +57,11 @@
 /* This just needs to be "large enough" */
 #define G_BDE_KEYBYTES	304
 
+/* This file is being included by userspace. */
+#ifndef __diagused
+#define	__diagused
+#endif
+
 struct g_bde_work;
 struct g_bde_softc;
 
@@ -176,7 +181,7 @@ void g_bde_worker(void *arg);
 static __inline void
 AES_init(cipherInstance *ci)
 {
-	int error;
+	int error __diagused;
 
 	error = rijndael_cipherInit(ci, MODE_CBC, NULL);
 	KASSERT(error > 0, ("rijndael_cipherInit %d", error));
@@ -185,7 +190,7 @@ AES_init(cipherInstance *ci)
 static __inline void
 AES_makekey(keyInstance *ki, int dir, u_int len, const void *key)
 {
-	int error;
+	int error __diagused;
 
 	error = rijndael_makeKey(ki, dir, len, key);
 	KASSERT(error > 0, ("rijndael_makeKey %d", error));
@@ -194,7 +199,7 @@ AES_makekey(keyInstance *ki, int dir, u_int len, const void *key)
 static __inline void
 AES_encrypt(cipherInstance *ci, keyInstance *ki, const void *in, void *out, u_int len)
 {
-	int error;
+	int error __diagused;
 
 	error = rijndael_blockEncrypt(ci, ki, in, len * 8, out);
 	KASSERT(error > 0, ("rijndael_blockEncrypt %d", error));
@@ -203,7 +208,7 @@ AES_encrypt(cipherInstance *ci, keyInstance *ki, const void *in, void *out, u_in
 static __inline void
 AES_decrypt(cipherInstance *ci, keyInstance *ki, const void *in, void *out, u_int len)
 {
-	int error;
+	int error __diagused;
 
 	error = rijndael_blockDecrypt(ci, ki, in, len * 8, out);
 	KASSERT(error > 0, ("rijndael_blockDecrypt %d", error));

sys/geom/journal/g_journal.c

@@ -2961,7 +2961,7 @@ g_journal_do_switch(struct g_class *classp)
 static void
 g_journal_start_switcher(struct g_class *mp)
 {
-	int error;
+	int error __diagused;
 
 	g_topology_assert();
 	MPASS(g_journal_switcher_proc == NULL);

sys/geom/shsec/g_shsec.c

@@ -249,11 +249,9 @@ g_shsec_xor1(uint32_t *src, uint32_t *dst, ssize_t len)
 static void
 g_shsec_done(struct bio *bp)
 {
-	struct g_shsec_softc *sc;
 	struct bio *pbp;
 
 	pbp = bp->bio_parent;
-	sc = pbp->bio_to->geom->softc;
 	if (bp->bio_error == 0)
 		G_SHSEC_LOGREQ(2, bp, "Request done.");
 	else {

sys/geom/stripe/g_stripe.c

@@ -203,7 +203,7 @@ static int
 g_stripe_access(struct g_provider *pp, int dr, int dw, int de)
 {
 	struct g_consumer *cp1, *cp2, *tmp;
-	struct g_stripe_softc *sc;
+	struct g_stripe_softc *sc __diagused;
 	struct g_geom *gp;
 	int error;
 

sys/geom/vinum/geom_vinum_create.c

@@ -552,11 +552,10 @@ gv_stripe(struct g_geom *gp, struct gctl_req *req)
 	struct gv_plex *p;
 	struct gv_softc *sc;
 	char *drive, buf[30], *vol;
-	int *drives, *flags, dcount, pcount;
+	int *drives, *flags, dcount;
 
 	sc = gp->softc;
 	dcount = 0;
-	pcount = 0;
 	vol = gctl_get_param(req, "name", NULL);
 	if (vol == NULL) {
 		gctl_error(req, "volume name not given");	

sys/geom/vinum/geom_vinum_init.c

@@ -233,7 +233,7 @@ gv_find_good_plex(struct gv_volume *v)
 static int
 gv_sync(struct gv_volume *v)
 {
-	struct gv_softc *sc;
+	struct gv_softc *sc __diagused;
 	struct gv_plex *p, *up;
 	int error;
 

sys/geom/vinum/geom_vinum_plex.c

@@ -538,10 +538,8 @@ gv_normal_parity(struct gv_plex *p, struct bio *bp, struct gv_raid5_packet *wp)
 static void
 gv_plex_flush(struct gv_plex *p)
 {
-	struct gv_softc *sc;
 	struct bio *bp;
 
-	sc = p->vinumconf;
 	bp = bioq_takefirst(p->rqueue);
 	while (bp != NULL) {
 		gv_plex_start(p, bp);

sys/geom/vinum/geom_vinum_raid5.c

@@ -345,15 +345,12 @@ static int
 gv_raid5_request(struct gv_plex *p, struct gv_raid5_packet *wp,
     struct bio *bp, caddr_t addr, off_t boff, off_t bcount, int *delay)
 {
-	struct g_geom *gp;
 	struct gv_sd *broken, *original, *parity, *s;
 	struct gv_bioq *bq;
 	struct bio *cbp;
 	int i, psdno, sdno, type, grow;
 	off_t real_len, real_off;
 
-	gp = bp->bio_to->geom;
-
 	if (p == NULL || LIST_EMPTY(&p->subdisks))
 		return (ENXIO);
 

sys/geom/vinum/geom_vinum_rename.c

@@ -226,7 +226,7 @@ int
 gv_rename_vol(struct gv_softc *sc, struct gv_volume *v, char *newname,
     int flags)
 {
-	struct g_provider *pp;
+	struct g_provider *pp __diagused;
 	struct gv_plex *p;
 	char newplex[GV_MAXPLEXNAME], *ptr;
 	int err;

sys/geom/vinum/geom_vinum_subr.c

@@ -1124,7 +1124,7 @@ int
 gv_attach_plex(struct gv_plex *p, struct gv_volume *v, int rename)
 {
 	struct gv_sd *s;
-	struct gv_softc *sc;
+	struct gv_softc *sc __diagused;
 
 	g_topology_assert();
 

sys/geom/vinum/geom_vinum_volume.c

@@ -59,12 +59,10 @@ gv_volume_flush(struct gv_volume *v)
 void
 gv_volume_start(struct gv_softc *sc, struct bio *bp)
 {
-	struct g_geom *gp;
 	struct gv_volume *v;
 	struct gv_plex *p, *lp;
 	int numwrites;
 
-	gp = sc->geom;
 	v = bp->bio_to->private;
 	if (v == NULL || v->state != GV_VOL_UP) {
 		g_io_deliver(bp, ENXIO);
@@ -143,7 +141,7 @@ gv_volume_start(struct gv_softc *sc, struct bio *bp)
 void
 gv_bio_done(struct gv_softc *sc, struct bio *bp)
 {
-	struct gv_volume *v;
+	struct gv_volume *v __diagused;
 	struct gv_plex *p;
 	struct gv_sd *s;
 

sys/geom/virstor/g_virstor.c

@@ -1528,11 +1528,9 @@ g_virstor_dumpconf(struct sbuf *sb, const char *indent, struct g_geom *gp,
 static void
 g_virstor_done(struct bio *b)
 {
-	struct g_virstor_softc *sc;
 	struct bio *parent_b;
 
 	parent_b = b->bio_parent;
-	sc = parent_b->bio_to->geom->softc;
 
 	if (b->bio_error != 0) {
 		LOG_MSG(LVL_ERROR, "Error %d for offset=%ju, length=%ju, %s",